<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>

    <style>
        #iddiv{
            background-color: aqua;
        }
        .cdiv{
            background-color: blue;
        }
        div{ 
            background-color: red;
        }

        /* id 选择器权重> class>元素*/

        /* 包含选择器 */
        div p{
            background-color: blueviolet;
        }

    </style>

</head>
<body>
    
    <div class="cdiv" id="iddive">
        1111111111111
    </div>

    <div>

        <p>ssssssssssss</p>

    </div>

</body>
</html>